Supported pure?() method.

Supported `fallback to pure` feature on JRuby.

lib/fuzzystringmatch.rb

@@ -17,7 +17,11 @@
 #
 require 'fuzzystringmatch/pure'
 begin
-  require 'fuzzystringmatch/inline'
+  if RUBY_PLATFORM == "java"
+    STDERR.puts "Warning: native version is disabled on java platform. falled back to pure ruby version..."
+  else
+    require 'fuzzystringmatch/inline'
+  end
 rescue LoadError
 end
 

lib/fuzzystringmatch/inline/jarowinkler.rb

@@ -18,6 +18,10 @@
 module FuzzyStringMatch
   require 'inline'
   class JaroWinklerInline
+    def pure?
+      false
+    end
+
     inline do |builder|
       builder.include '<iostream>'
       builder.add_compile_flags '-x c++', '-lstdc++'

lib/fuzzystringmatch/pure/jarowinkler.rb

@@ -19,6 +19,10 @@ module FuzzyStringMatch
   class JaroWinklerPure
     THRESHOLD = 0.7
 
+    def pure?
+      true
+    end
+
     def getDistance( s1, s2 )
       a1 = s1.split( // )
       a2 = s2.split( // )

test/basic_native_spec.rb

@@ -46,5 +46,7 @@
       d2 = @jarow.getDistance("brittney spears", "brittney startzman")
       d1 > d2
     }.should be_true
+
+    @jarow.pure?( ).should == (RUBY_PLATFORM == "java")
   end
 end

test/basic_pure_spec.rb

@@ -46,5 +46,7 @@
       d2 = @jarow.getDistance("brittney spears", "brittney startzman")
       d1 > d2
     }.should be_true
+
+    @jarow.pure?( ).should be_true
   end
 end

test/mutibyte_spec.rb

@@ -52,5 +52,7 @@
     @jarow.getDistance( "まつもとゆきひろ",          "まつもとひろゆき"           ).should be_within(0.0001).of(0.9500)
     @jarow.getDistance( "クライエント",              "クライアント"               ).should be_within(0.0001).of(0.9222)
     @jarow.getDistance( "サーバー",                  "サーバ"                     ).should be_within(0.0001).of(0.9416)
+
+    @jarow.pure?( ).should be_true
   end
 end